
		\centering
		\begin{center}
			\begin{tikzpicture}[-stealth,scale=2,transform shape,node distance = 1em]
				\tikzstyle{every node}=[font=\small,scale=0.8]
				\begin{scope}[minimum height = 1pt]
					\tikzstyle{inout}=[trapezium, trapezium left angle=60, trapezium right angle=120, draw] %%输入输出框
					\tikzstyle{point}=[coordinate,on grid,] % 像素点,用于连接转移线
					\tikzstyle{mid}=[rectangle,  opacity=0,draw] 
					\tikzstyle{end}=[rectangle, rounded corners, draw]   %%教材上的起止框
					\tikzstyle{endn}=[rounded rectangle, draw]   %%新版的起止框
					\tikzstyle{exec}=[rectangle, draw]    %%执行框 execute
					\tikzstyle{io} = [trapezium, trapezium left angle=70, trapezium right angle=110, minimum width=3cm, minimum height=1cm, text centered, draw=black]  % 平行四边形
					\tikzstyle{decide}=[diamond,aspect=2,draw,thin]   %%判断框 opacity=0.3
					
					% 节点 直线
					\node[end] (s) at (0,0) {入口};
					\node[decide] (d1) at ([yshift=-2em]s.south) {E};
					\node[exec] (e1) at ([yshift=-2em]d1.south) {执行S};
					
					% 右边
					\node[end] (e2) at ([xshift=2em,yshift=-1em]e1.east) {出口};
					
					
					
					% % 连线 
					\draw (s) -- (d1.north);
					\draw (d1.south) -- node[right]{true}(e1.north);
					\draw (e1.south) -- ([yshift=-1em]e1.south) -- ([xshift=-2em,yshift=-1em]e1.south) -- ([xshift=-2em,yshift=5em]e1.south) -- ([xshift=0em,yshift=5em]e1.south);
					% \draw (e1.south) -- (end.north);
					
					% % % 右边斜线
					\draw (d1.east) -| node[above]{false}(e2.north);
					
				\end{scope}
			\end{tikzpicture}
		\end{center}
